It's possible that this is a Tex size, which would make it between size 92 and size 138, but I don't know for sure.
My advise to you and to anyone who gets thread with a machine or has it given to them is, and always will be, to throw it away and buy new thread. Why ruin an entire project by using suspect thread? For the price of a small spool of thread, it just isn't worth it.
No one lives forever, the trick is creating something that will.